Export Powerpoint slides at 300 DPI- not working

Hi LE

According to my research, PowerPoint normally exports slides at 96 DPI unless the ExportBitmapResolution registry value is correctly configured and the slide is exported using a method that supports this setting.

Please check the following:

Verify that the registry value was created under the correct key for Office 2021:

HKEY_CURRENT_USER\Software\Microsoft\Office\16.0\PowerPoint\Options
``

Create a DWORD (32-bit) value named: ExportBitmapResolution

Set Base = Decimal and Value data = 300. Office 2021 uses the same 16.0 registry branch as Office 2016/2019/Microsoft 365.

• After making the registry change, completely close PowerPoint and reopen it. If the issue persists, restart Windows and test again. PowerPoint may not read the updated value until it is restarted. 
• Export the slide using File > Save As (or File > Export) and select JPEG/PNG. The registry setting does not apply to every image-saving method, such as some Save as Picture operations.
• Check the exported image's pixel dimensions, not just the DPI value shown in File Properties. For example, a standard widescreen slide (13.333" × 7.5") exported at 300 DPI should be approximately: 4000 × 2250 pixels

For your information, you can refer to: Export PowerPoint Slides At Higher DPI For Better Print Quality - SysTutorials

(This link above is shared by community members for your convenience. They point to third-party sites that are not managed or verified by Microsoft. I cannot guarantee the quality, safety, or suitability of any content or software found there. Please review them carefully for reference and make sure you understand any potential risks before using them)

If the exported image is still around 1280 × 720 pixels, PowerPoint is likely exporting at the default resolution. If the registry entry is correct and the output remains unchanged, try running an Online Repair of Office and test again. Similar cases have been resolved after repairing the Office installation. (Repair an Office application | Microsoft Support)

As a related discussion, you may also find this thread helpful: Export High Quality (300DPI) Image From Powerpoint. - Microsoft Q&A

Could you also confirm whether the exported JPEG shows only 96 DPI in its properties, or whether the pixel dimensions are also lower than expected?

I hope this information helps and look forward to your response.